Both lobelia and sweet alyssum (Lobularia maritima) are quite shade tolerant and fast and easy to grow from seed. And they will nicely compliment most other shade annuals that are larger and more easily planted as starts, so you can do some of both :-)

Alright, we'll give these ones a try! Thanks for the recommendation

If you can find Impatiens balsamina (aka garden balsam) you might want to try that. The lack of sun won't be ideal but they'll sprout and grow quickly, and if they flower and manage to set seed, the seed pods are great run for kids to pop. :)

Torenia and mimulus. They are a bit more interesting than impatients and vinca IMHO.

Mimulus can start blooming within a month